1. Field of the Invention
The present invention relates to a backlight module for a display device, in particular, to a backlight module with light uniform design for a display device.
2. Description of the Prior Art
In recent years, the liquid crystal display (LCD) technology is more mature. With the increase of the preferences and demands of consumers, the LCDs also gradually become thinner. In order to achieve a thinner LCD, various components of the LCD, such as display panel, optical film and backlight module, should be reduced in thickness. Because the backlight module needs a light mixing space, a required thickness for the backlight module is usually large, and thus the main target is to reduce the thickness of the backlight module.
FIG. 1A shows a thin type of direct lighting backlight module. As shown in FIG. 1A, a plurality of light-emitting diode (LED) light sources 13 are placed on the carrier plate 10. A reflective film 30 is disposed above the LED light sources 13. A plurality of holes 31 are formed in the reflective film 30. The light generated by LED light sources 13 is reflected back and forth between the reflective film 30 and the carrier plate 10 and is emitted via different holes 31 to achieve the purpose of dispersing the light source. In addition, a diffusion plate 50 is disposed above the reflective film 30. The diffusion plate 50 is supported by a plurality of support members 11, which are disposed on the carrier plate 10 and pass through the holes 31, and the light leaving from the reflective film 30 and passing through the diffusion plate 50 can produce uniform backlighting.
FIG. 1B shows a top view of the reflective film 30. As shown in FIG. 1B, the reflective film 30 includes multiple blocks 33, and the holes 31 in each block 33 are arranged with same arrangement. In the central part of the reflective film 30, since the amount of light in a position adjacent to each of the blocks 33 can be complemented by adjacent blocks 33, the uniformity of light distribution still can be maintained. However, in the edge of the reflective film 30, because of no adjacent blocks 33 to complement the amount of light, there will be a more obvious distribution with bright regions 35 and dark regions 37.